A WirelessHD standard has been drawn up for wirelessly transmitting uncompressed baseband video signals and uncompressed digital audio signals among audio and visual devices (referred to as AV (Audio and Visual) devices hereinafter). The WirelessHD is a technical specification for viewing high-definition moving image data stored in a source device such as a digital video recorder, a set-top box or a personal computer on a sink device such as a high-definition television without connecting the source device to the sink device via a cable. In addition, since control signals are transmitted bi-directionally, it is possible to control a television set and a digital video recorder so as to cooperate with each other, or it is possible to construct a home theater by a plurality of AV devices and control the same AV devices integrally. In addition, protocols for these controls are defined. Further, since it is possible to transmit high-quality contents by the WirelessHD, DTCP (Digital Transmission Content Protection) is defined as a content protection method so that provided contents are not illegally reproduced or illegally replicated. For example, wireless transmission methods compliant with the WirelessHD according to prior art are described in Patent Documents 1 and 2, and a Non-patent Document 1. In addition, methods of wirelessly transmitting AV data according to prior art are described in Patent Documents 3 and 4.